[PATCH RFC v2 1/2] drm: Add optinal YCBCR_ENCODING property to drm_plane

Jyri Sarha jsarha at ti.com
Thu May 4 07:14:25 UTC 2017


Add a standard optinal property to control YCbCr conversion in DRM
planes. The property is stored to drm_plane object to allow different
set of supported conversion modes for different planes on the device.

Signed-off-by: Jyri Sarha <jsarha at ti.com>
---
 drivers/gpu/drm/drm_atomic.c     |  5 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 59 ++++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_plane.c      |  3 ++
 include/drm/drm_color_mgmt.h     | 14 ++++++++++
 include/drm/drm_plane.h          |  6 ++++
 5 files changed, 87 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 4033384..bcef93d 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -732,6 +732,7 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 {
 	struct drm_device *dev = plane->dev;
 	struct drm_mode_config *config = &dev->mode_config;
+	int ret;
 
 	if (property == config->prop_fb_id) {
 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, val);
@@ -774,6 +775,8 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->ycbcr_encoding_property) {
+		state->ycbcr_encoding = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);
@@ -834,6 +837,8 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->ycbcr_encoding_property) {
+		*val = state->ycbcr_encoding;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {
diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c
index 533f3a3..245b14a 100644
--- a/drivers/gpu/drm/drm_color_mgmt.c
+++ b/drivers/gpu/drm/drm_color_mgmt.c
@@ -33,6 +33,11 @@
  * properties on the &drm_crtc object. They are set up by calling
  * drm_crtc_enable_color_mgmt().
  *
+ * Support for different YCbCr color encodings is controlled trough
+ * plane specific YCBCR_ENCODING property.
+ *
+ * The &drm_crtc object's properties are:
+ *
  * "DEGAMMA_LUT”:
  *	Blob property to set the degamma lookup table (LUT) mapping pixel data
  *	from the framebuffer before it is given to the transformation matrix.
@@ -85,6 +90,13 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * The &drm_plane object's properties are:
+ *
+ * "YCBCR_ENCODING"
+ * 	Optional plane enum property to control YCbCr to RGB
+ * 	conversion. The driver provides a subset of standard
+ *	enum values supported by the DRM plane.
  */
 
 /**
@@ -333,3 +345,50 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static char *ycbcr_encoding_name[] = {
+	[DRM_PLANE_YCBCR_BT601_FULL_RANGE] = "BT.601 full range",
+	[DRM_PLANE_YCBCR_BT601_LIMITED_RANGE] = "BT.601 limited range",
+	[DRM_PLANE_YCBCR_BT709_LIMITED_RANGE] = "BT.709 limited range",
+	[DRM_PLANE_YCBCR_BT2020_LIMITED_RANGE] = "BT.2020 limited range",
+};
+
+/**
+ * drm_plane_create_ycbcr_properties - ycbcr related plane properties
+ * @enum_list: drm_prop_enum_list array of supported modes without names
+ * @enum_list_len: length of enum_list array
+ * @default_mode: default YCbCr encoding
+ *
+ * Create and attach plane specific YCBCR_ENCODING property to to the
+ * drm_plane object. The supported encodings should be provided in the
+ * enum_list parameter. The enum_list parameter should not contain the
+ * enum names, because the standard names are added by this function.
+ */
+int drm_plane_create_ycbcr_properties(struct drm_plane *plane,
+			struct drm_prop_enum_list *enum_list,
+			unsigned int enum_list_len,
+			enum drm_plane_ycbcr_encoding default_mode)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	unsigned int i;
+
+	if (WARN_ON(plane->ycbcr_encoding_property != NULL))
+		return -EEXIST;
+
+	for (i = 0; i < enum_list_len; i++) {
+		enum drm_plane_ycbcr_encoding encoding = enum_list[i].type;
+
+		enum_list[i].name = ycbcr_encoding_name[encoding];
+	}
+
+	prop = drm_property_create_enum(dev, DRM_MODE_PROP_ATOMIC,
+					"YCBCR_ENCODING",
+					enum_list, enum_list_len);
+	if (!prop)
+		return -ENOMEM;
+	plane->ycbcr_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_mode);
+
+	return 0;
+}
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index fedd4d6..007c4d7 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -244,6 +244,9 @@ void drm_plane_cleanup(struct drm_plane *plane)
 
 	kfree(plane->name);
 
+	if (plane->ycbcr_encoding_property)
+		drm_property_destroy(dev, plane->ycbcr_encoding_property);
+
 	memset(plane, 0, sizeof(*plane));
 }
 EXPORT_SYMBOL(drm_plane_cleanup);
diff --git a/include/drm/drm_color_mgmt.h b/include/drm/drm_color_mgmt.h
index 03a59cb..1771394 100644
--- a/include/drm/drm_color_mgmt.h
+++ b/include/drm/drm_color_mgmt.h
@@ -26,6 +26,8 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
+struct drm_prop_enum_list;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 
@@ -37,4 +39,16 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_plane_ycbcr_encoding {
+	DRM_PLANE_YCBCR_BT601_FULL_RANGE = 0,
+	DRM_PLANE_YCBCR_BT601_LIMITED_RANGE,
+	DRM_PLANE_YCBCR_BT709_LIMITED_RANGE,
+	DRM_PLANE_YCBCR_BT2020_LIMITED_RANGE,
+};
+
+int drm_plane_create_ycbcr_properties(struct drm_plane *plane,
+			struct drm_prop_enum_list *enum_list,
+			unsigned int enum_list_len,
+			enum drm_plane_ycbcr_encoding default_mode);
+
 #endif
diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
index 9ab3e70..4d0510f 100644
--- a/include/drm/drm_plane.h
+++ b/include/drm/drm_plane.h
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;
@@ -112,6 +113,9 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* YCbCr to RGB conversion */
+	enum drm_plane_ycbcr_encoding ycbcr_encoding;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 
@@ -523,6 +527,8 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *ycbcr_encoding_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)
-- 
1.9.1



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